In this article we will discuss:- 1. Meaning of tRNA 2. Structure of tRNA 3. Initiator Transfer RNA. Meaning of tRNA: Transfer RNAs (tRNAs), also called "soluble RNAs" (sRNAs) are small molecules varying from 75 to 100 nucleotides in length. They carry amino acids and bring them to ribosomes to form the polypeptide chain. There are 20 amino acids but [...]
In this article we will discuss about the replication of genetic RNA. Several viruses and bacteriophages contain single- or double-stranded RNA as their genetic material (Table 3.1). Replication of these RNA chromosomes occurs in the host cytoplasm following one of the two modes given below: (i) Direct use of RNA template for RNA synthesis (RNA RNA) by the enzyme -'RNA [...]
The following points highlight the four main stages involved in synthesis of RNA. The stages are: 1. Binding of RNA Polymerase to DNA 2. Initiation of Transcription 3. Elongation of RNA chain 4. Termination of Transcription. Stage # 1. Binding of RNA polymerase to DNA: RNA polymerase binds to the "promoter site" on the DNA molecule. The promoter site is [...]